Ophthalmology >>>> Retinitis pigmentosa

Retinitis pigmentosa.

Retinitis pigmentosa is a disease that affects the retinal pigment epithelium and retinal photoreceptors. Retinitis pigmentosa develops from early childhood (up to eight years), slowly progresses. Most often, the disease develops in men. Blindness occurs by the age of forty or sixty. It is believed that retinal dystrophies of different localization are a consequence of mutations in the genes of periphirin and rhodopsin (the first identified gene responsible for mutations). Retinal dystrophy is accompanied by the death of the neuroepithelium (neurons are replaced by cells of the pigment epithelium) and the narrowing of the retinal vessels. The replacement process is moving steadily from the periphery of the retina to the center. With retinitis pigmentosa, the twilight vision apparatus perishes.

The disease is referred to as hereditary generalized retinal dystrophies . There are several ways of inheriting the disease: autosomal dominant (pathology is transmitted from one parent), autosomal recessive (when the genes of the disease are passed on to offspring from both parents) or sex-related (transmitted to the son from the mother with the X chromosome). To date, eleven regions of chromosomes have been found containing genes, the mutation of which causes the development of retinitis pigmentosa .

Three characteristic signs are considered clinical manifestations of the disease:

Pigmented foci appear in the peripheral areas of the fundus and along the path of venules (the so-called bone corpuscles),
Waxy blanching of the optic nerve head,
Narrowing of arterioles.

Retinitis pigmentosa signs:

A typical symptom of dystrophic phenomena in the retina is a violation of twilight vision or, as this phenomenon is called in everyday life, night blindness ;
Narrowing of the field of vision;
Decreased central vision;
Decreased visual acuity;
Raising the threshold of light sensitivity;
In atypical forms of retinitis pigmentosa, photophobia appears, central and color vision decreases (pigmentary inverted retinitis).

Treatment of retinal dystrophy today does not have any justified substitution or stimulatory therapy. Treatment is prescribed according to the symptoms:

For macular edema - diuretics (carbonic anhydrase inhibitors);
In case of clouding of the lens, surgery is performed in the treatment of cataracts to improve visual acuity;
Prescribe vascular pharmaceuticals, recommend vascular photocoagulation;
Carry out vitamin therapy , especially focus on the intake of niacin;
Shown a diet to reduce cholesterol and purine compounds.

There are scientific developments (experimental) on the method of transplantation of pigment epithelium cells and retinal neuronal cells from an embryo of one week old. Methods of gene therapy are being developed - the introduction of an adenovirus carrying healthy minichromosomes. So far, all research is at the development stage.